1. Technical Field
The present invention relates to a printer that runs a printing process based on print data sent from a host computer, to a printer system, and to a method for rewriting printer firmware.
2. Related Art
The print mechanism, paper transportation mechanism, and other operations in a printer are controlled by firmware. The firmware is stored in the printer in ROM or flash memory, for example. Firmware is not frequently changed, but can usually be rewritten to add new functions or to correct bugs in existing functions, for example.
Multiple printers are commonly connected to and used over a LAN, and each printer must be running the same firmware in order to maintain a common operating environment across all printers. In order to rewrite the firmware in each of the plural printers connected to a network, Japanese Unexamined Patent Appl. Pub. JP-A-2001-216115 teaches broadcasting the rewrite data from a host computer to all of the printers, each of which then runs a firmware rewriting process to update the firmware based on the received rewrite data.
In order to ensure that each printer executes the same rewriting process when rewriting firmware in a plurality of printers, the rewrite operation is determined to have failed if only one printer fails to rewrite the firmware even though all other printers have successfully rewritten the firmware. This then requires all printers to repeat the firmware rewriting operation. Rewriting the firmware can fail when an internal printer error is caused by an ink end, no paper, or open cover error, for example, and the printer is in a standby state waiting for the error to be corrected, or the printer is in the middle of a print job and the rewrite data cannot be received into the receive buffer of the printer.
If the printer system has numerous printers connected to a central server such as in a retail store, ink end errors and other types of errors occur frequently and many printers are typically executing a print job at any particular time. As a result, rewriting the firmware can be rendered practically impossible if the rewriting operation must wait until all printers can run the firmware rewriting process at the same time.